Foundation Considerations: Tear Down or Remodel?
I am considering a new project but have some concerns about the site and how to handle the existing structure, which is a casually built lakeside “cottage.”
This structure is about 800 square feet (20 x 40 feet) and probably 60+ years old. It’s a dump, but the site is nice.
My original plan was to remodel and add on an additional 800 of living space. The crawlspace foundation is all masonry units, which seems to be in good condition. But I also noticed there are no footings. The block walls are resting on clay soil.
The soil is not expansive and the foundation looks stable, but I can’t imagine keeping it. Can you? Maybe I could install a bulkhead as a substitute for the missing footers. But that would all be handwork.
Access this site very limited. The “main road” is really a poorly paved and curvy goat path less than 8 feet wide. If the project moves forward, I’m leaning toward taking everything down, eliminating the crawl, and using piers for the new foundation.
The neighbors would probably revolt if I tried to bring in a pumper truck for a poured foundation.
Thoughts for moving forward?
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Steve, generally speaking, when building a house, everything depends on having a good foundation. It's not a good place to cut quality. However, there is a chance it's usable; are there crushed stone footings? The IRC allows them, see table R403.1: https://codes.iccsafe.org/content/IRC2018/chapter-4-foundations#IRC2018_Pt03_Ch04_SecR403.
Hi Michael,
I suspect there is no crushed stone. While walking around the foundation, I found a corner where an armadillo had recently tunneled into the crawlspace. (Aren't you glad to be living in Maine?) The hole wasn't particularly deep, which is what made me realize the footings were missing. And I didn't see any stone but will give it a closer look next time I am there.
It's easy to visually miss crushed stone that has been underground for a long time because other, smaller sediment tends to migrate into the stone and then it doesn't look like stone as much anymore. This is why you have socks on drain tile, for example -- to help keep fine sediment from migrating in and clogging things.
It's easy to tell if there is stone with a shovel though -- crushed stone is lots harder to dig into compared with loose soil. If you can get to it, try jamming in a shovel and see what you find. I suspect you might not find much though, since critters would have a harder time tunneling through crushed stone than loose soil too.
Bill
Just to close the loop on this thread... I had the house inspected, and the visit confirmed that there were no footers under the block walls or masonry chimney. There also wasn't any waterproofing on any of the foundation walls (and the septic needed to be replaced and moved to meet current code). All together, it made more sense to tear everything down and start over. Because of limited access, demoing the existing structures was going to be expensive. Unfortunately, the seller would not agree to a price reduction and we had to pass on the property.